And considering the park sits on a supervolcano, it sounds bad. But swarms of tiny earthquakes are actually normal at Yellowstone.
Experts with the U.S. Geological Survey say swarms account for about half of the park's seismic activity each year and that they don't make the volcano any more likely to erupt.
Experts say if Yellowstone was about to erupt, there would be more troubling signs. Magma rising to the surface might cause more frequent and stronger earthquakes than those from this swarm. And the ground might deform, or there might be more steam venting.
But there's also no way to forecast how or when an eruption might happen for sure. Keep that in mind the next time you're watching Old Faithful.